Osteoarthritis is a degenerative joint disease characterized by abnormal wearing of cartilage that covers and cushions the joint and the destruction or decrease in synovial fluid that lubricates the joint. Treatment for this condition includes injections of medication into the joint which supplements the viscosity of the joint fluid, lubricates and cushions the joint, and produces an analgesic effect. Medication, such as hyaluronic acid, can also have a positive biochemical effect on cartilage cells by slowing or even reversing their deterioration. The key to such treatment is to ensure that the injection is provided precisely into the synovial joint. If the injection is not provided precisely into the synovial joint, the efficacy of the treatment suffers severely. The current technique for locating the needle in this joint is by “feel” of a practiced physician. Studies by Jackson et al. (JBJS 2002) have shown that 30% of the hyaluronic acid injections in knees are improperly placed.
Epidural injections and anesthesia are often given to patients without proper guidance. In particular, proper guidance is necessary for intra-operative anesthesia and for labor and delivery. Improper placement of these procedures can cause dural punctures in up to 1% of individuals. Dural punctures can lead to severe headaches and a need for a blood patch. In rare instances, accidental intravascular injectate may result in paralysis.